Flea beetles are one of the most jarring canola pests in the northern Plains. Follow these guidelines to control infestations.
Factors to Consider
- Late-season flea beetle presence
- Planting date
- Early season canola vigor
- Seed treatment
- Field scouting
- Identify the insect. There are two species of flea beetles that infest canola fields: striped and crucifer flea beetles. Both species are about 1⁄20 inch long and jump when disturbed. The striped flea beetle is black with two cream-colored stripes along its back. The crucifer flea beetle is bluish-black with no stripes.
- Understand the life cycle. Flea beetles overwinter as adults and emerge in the early spring. When temperatures reach 70 F, flea beetles become active and fly into developing canola fields where they feed on new plants.
- Scout for damage. Monitor newly emerged canola fields daily for flea beetle feeding and to evaluate the damage occurring in fields. Flea beetles damage plants early in the growth stage, feeding on emerging cotyledons and first true leaves. Closely monitor fields until plants are past the four-leaf stage. Symptoms of a flea beetle infestation include thinning stands, notches at leaf edges, circular pits on the leaf surface and seedlings eaten at or below ground level.
- Consider management options. Plant canola early to allow canola to develop before the threat of flea beetles occurs. Seed-applied insecticides are widely available and can be effective in controlling flea beetles during the first few weeks of growth. Flea beetle damage can occur quickly, so immediate action with the ability to cover acres quickly is important. Apply foliar treatment when injury is approaching 25 percent and beetles are present.
Flea beetles are destructive to canola stands and potential yield. Good management practices, seed treatment and vigilant scouting can protect canola stands and grower investments. For more information, contact your local Mycogen Seeds customer agronomist or trusted agronomic adviser.